1/* SPDX-License-Identifier: GPL-2.0 */
2
3/* Try to choose an implementation variant via Kconfig */
4#ifdef CONFIG_CRC32_SLICEBY8
5# define CRC_LE_BITS 64
6# define CRC_BE_BITS 64
7#endif
8#ifdef CONFIG_CRC32_SLICEBY4
9# define CRC_LE_BITS 32
10# define CRC_BE_BITS 32
11#endif
12#ifdef CONFIG_CRC32_SARWATE
13# define CRC_LE_BITS 8
14# define CRC_BE_BITS 8
15#endif
16#ifdef CONFIG_CRC32_BIT
17# define CRC_LE_BITS 1
18# define CRC_BE_BITS 1
19#endif
20
21/*
22 * How many bits at a time to use. Valid values are 1, 2, 4, 8, 32 and 64.
23 * For less performance-sensitive, use 4 or 8 to save table size.
24 * For larger systems choose same as CPU architecture as default.
25 * This works well on X86_64, SPARC64 systems. This may require some
26 * elaboration after experiments with other architectures.
27 */
28#ifndef CRC_LE_BITS
29# ifdef CONFIG_64BIT
30# define CRC_LE_BITS 64
31# else
32# define CRC_LE_BITS 32
33# endif
34#endif
35#ifndef CRC_BE_BITS
36# ifdef CONFIG_64BIT
37# define CRC_BE_BITS 64
38# else
39# define CRC_BE_BITS 32
40# endif
41#endif
42
43/*
44 * Little-endian CRC computation. Used with serial bit streams sent
45 * lsbit-first. Be sure to use cpu_to_le32() to append the computed CRC.
46 */
47#if CRC_LE_BITS > 64 || CRC_LE_BITS < 1 || CRC_LE_BITS == 16 || \
48 CRC_LE_BITS & CRC_LE_BITS-1
49# error "CRC_LE_BITS must be one of {1, 2, 4, 8, 32, 64}"
50#endif
51
52/*
53 * Big-endian CRC computation. Used with serial bit streams sent
54 * msbit-first. Be sure to use cpu_to_be32() to append the computed CRC.
55 */
56#if CRC_BE_BITS > 64 || CRC_BE_BITS < 1 || CRC_BE_BITS == 16 || \
57 CRC_BE_BITS & CRC_BE_BITS-1
58# error "CRC_BE_BITS must be one of {1, 2, 4, 8, 32, 64}"
59#endif
60